Abstract: We examine of the capability of the Next Linear Collider to determine the mass as well as the couplings to leptons and $b$-quarks of a new neutral gauge boson, $Z'$, below direct production threshold. By using simulated data collected at several different values of $\sqrt s$, we demonstrate how this can be done in a model-independent manner via an anonymously case approach. The importance of beam polarization to the success of this program is discussed. The procedure is shown to be easily extended to the case of top and charm quark couplings.